Shell script cannot test for the existence of files

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© July 2015 Anthony Lawrence

Anonymous asks:

My shell script needs to move certain files to another location. How do I test that the files exist?

The script you supplied looks like this:

if [ -f /home/sales/*.xml ]
 then

 mv /home/sales/*.xml /tmp

fi
 

Your problem is that "/home/sales/*.xml" can expand to more than one file. The "mv" doesn't care, but test ("[") can't handle that. That's why your script won't work.

You can do this instead:

for i in  /home/sales/*.xml
do
mv $i /tmp
done
 

If there is nothing in /home/sales to match *.xml, the loop won't move anything, but will error. To suppress the errror add "2>/dev/null after the "done".

An equivalent loop in Perl doesn't need the error redirection:

#!/usr/bin/perl
@files=<foobahjj*>;
foreach  (@files) {
  # Nothing in this loop will execute if there are no foobahjj* files.
  print $_
  print "goo"
}
 

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